1. Field of the Invention
The present invention relates, in general, to air conditioning systems. In particular, the invention relates to a multiple type air conditioning system including a plurality of internal units (air conditioning units) and one external unit (refrigerant supply unit) which respectively supplies refrigerant to the plurality of internal units.
2. Description of the Related Art
A conventional multiple type air conditioning system typically includes one external unit and a plurality of internal units to supply conditioned air to different spaces to be air-conditioned. In this type of the air conditioning system, increase in the internal unit has been desired to meet with increase in the space to be air-conditioned. In addition, an internal unit which has a small air conditioning capacity is also increased as a personal air conditioning. In this circumstances, the air conditioning capacity of the internal unit is subdivided, and connecting pipes having a different diameter are employed to supply sufficient amount of refrigerant to each subdivided internal unit. Junction point of the connecting pipes is also increased.
In the above-described conventional multiple air conditioning system, since the refrigerant flow to each internal unit is greatly varied because of the different flow resistance in each connecting pipe, an appropriate distribution of refrigerant to each internal unit may not be achieved. Such an undistribution of refrigerant adversely affects the air conditioning operation of each internal unit if the air conditioning capacity of each internal unit is small. The air conditioning capacity of the internal unit having a small air conditioning capacity is greatly changed and a stable air conditioning may not be obtained.